Hello and welcome to the Fitbit Community @Weburt
I understand you’re Fitbit Tracker has lost steps. If you feel like your Fitbit is not syncing properly let’s try restarting your Fitbit Tracker to see if that resolves the issue. Please look here for the proper way to perform a restart: https://help.fitbit.com/articles/en_US/Help_article/1186
😃 Please let me know if this helps. Keep me posted.
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